/** 封装获取远程JS返回的JSON数据 **/
export const getJson = (url, func, callback) => {
  window[func] = function(data) {
    callback(data)
  }
  const script = document.createElement('script')
  script.setAttribute('src', url)
  document.getElementsByTagName('head')[0].appendChild(script)
  script.onload = script.onreadystatechange = function(data) {
    window[func] = null
  }
}
